Combined electrical recorder and reproducer for phonographs



Dec. 1, 1931. o. M DUNNING 1,834,390

COMBINED ELECTRICAL RECORDER AND REPRODUCER FOR PHONOGRA'PHS Filed April 11, 1951 I FIG. 1

Patented Dec. 1, 1931 I UNITE FS ORVILLE M. DUNNING, E E As'r bEAEcnfrmw JERSEY, nss'reivon r0" meme;

PATENT- OFFICE;

EDISON, INCORPORATED, oE ;WEST. ORANGE, NE JERSEY, A CORPORATION, OF

:NEW JERSEY COMBINED ELEc'rnrcAL RECOBDER aniiEErEonUcE Eonrnonoenarns] A licatio filed April 11,

This invention. relates toa combined elec trical recorder and reproducer forphonographs such, for example, as dictating machines.

It is an object of thisinvention to provide an improved combination electrical recorder and reproducer which may be easily and simply operated by anyone without technical 7 experience.

sition';

It is a further object of this invention to provide such a combination electrical recorder and reproducer in which the armature and the moving system generally may'be made assmall and light as possible. 1

' It is a further object of this invention'to provide a combination electrical recorder and reproducer which will operate satlsfactorily with records of difiering diameter such,-for example, as may beencountered in the use of'business dictating machines where the records are shaved after use and used againand-again. v

It is a further object ofthis invention to provide a combination electrical recorder and reproducer which-will have the optlmum weight or. pressure upon the styli for both recording and reproducing and which. W111 at the same time have high sensitivity. j The features of novelty'which Ibelieve to be characteristic of my inventionare set forth with particularity in the appended, claims. My invention itself,:however,-bothas to 1ts fundamental principles and as to its par ticular embodiments, iwill best'be understood by reference to the specification and accompanying drawings, in-whi ch;

' Fig. 1 is a diagrammaticvlew of apparatus, according to this invention In recordlngfpog -Fig. 2- is a bottom plan view of thecombined unit;

- Fig. 8 is a larged scale, and p 7 Fig. 4 is a side elevation showing the appaf ratus in reproducing position. i-

In my application, Serial No. 466,902, filed, July 10', 1930, I have shown and described a combined electrical recorder and reproducer of the same general type as hereinreferred to; In the said application there is utilized a detail side elevation on an env The armature 1931'. Serial norszasss.

single combined operable either 'asa recorder or a reproducer and'selectively movbe obtainedby the use of 'an advanceball positionedu-pon the frame of the unit and travelingover an uncut portion of the record.

' It was further pointed out thatby' varying the position of the advance ball with respect to the recording stylus the desired pressure or'Weight-could be obtained upon the recording stylus regardless ofthe weight ofthe unit; that is to say, the desired proportion ofthetotal Weight of theunit supported by the stylus could be determined. The present invention relates to thesame general arrangement as already discussed, with which the change from recording toreproducing position is obtained by shifting'th'e position of the unit, and alsoconteniplates the supporting. of the unit in recording position by means of an advance'ball and" the recording tylus, and in reproducing position by the reproducingstylus only. '1 .1 I

In accordance with the present invention the advance ball is set alongside therecording stylus and is so adjusted or its height so chosen with reference to the recording stylus that said stylus engages the recordbefore it is engaged by the'advance ball. The height of the advanceballis so chosen that .itcomes into contact with the record when-the record ing stylus has penetrated a. predetermined distance into the recordj More specifically,

depth of the cutfdesired. g H 7 Referring now more particularly if it isdes ired to have the stylus cut-a groove of predetermined depth, the advance ball is l designates the combined recording and reproducingunit, the frame of which carries a pair of studs, 2 and 3 arranged to engage and hook into a depression in "the extension 4 of 11 carries a v reproducing stylus 9 and a recording stylus IO'and the advance ball 8 is mounted upon the frame of the unit directly alongside the recording stylus 10 and, of course, on the uncut side of the record.

The height of the advance ball is'so chosen and adjusted that the difference between the height of the two is equal to the depth of cut as already stated. Consequently, when the unit is in the position shown in 'Fig. 1 and is lowered upon the record, the recording stylus 10 will be forced into the record the correct distance. It cannot cutsany further into the record'because the engagement of the advance ball 8 with the record prevents suchaction.

\Vhile in the figures herein a cylindrical record has been shown, it will beunderstood that my invention is not limited to use with cylindrical records but is applicable to disc records also.

While I have not shown any specific form of. electromagnetic apparatus, it will be un derstood that the arrangements shown and described in the foregoing application .already referred to, may be utilized, or any satisfactory reversible electro-magnetic or; e'lectro-static or electro-dynamic apparatus maybe utilized wh'ichis capable of converting electric currents or potentials into me chanical vibrations and vice versa. Since many ,of these are well known in the art, and form per se no part of this invention, they are .not described in detail.

Also, the various-arrangements ofstyliand arms shown and described in the foregoing application may be utilized with this invention.

The unit is-carried by arm 5 to which the unit is pivoted .as at 12 so as to be rotatable and capable of being held in recording and reproducing positions respectively as shown in Figs. 1 and 4. The leverarm 5 is pivoted as at point 6 and may be provided with a counter-balance 7 .or .a spring may be utilized to lessen the pressure on the record if desired.

It will be noted that if the advance ball is not in a line precisely at right angles to the record groove and passing through the recording stylus, the depth of cut will be changed as the diameter of the record changes, due to achange of angle between the recorder and .the record. In order to minimize this change the pivot about which the arm 5swings should be placed in a line which is tangent to the surface of the average size record as shown in Fig. 1. It will be noted with reference to Fig. 1 that R and R represent maXimum and minimum record diamters. R is the mean of diameters R and R and the pivot 16 is preferably mounted on a line tangent to the surface of the record of mean diameter R While Ihave-shown and described certain preferred embodiments of my invention, it will be :understood that modifications and changes may bemade with out departing from the spirit and scope thereof as will be understood by those skilled in the art.

I claim:

1. A combined electrical sound recorder and reproducer unit, comprising, in combination, .a frame, a recording stylus carried by said frame, a reproducing stylus carried by said frame, reversible means for converting electric currents into mechanical vibrations associated, with said styli, an advance ball mounted on said frame, adjacent said recording stylus and on a line passing through the cutting face of said stylus and parallel to the lineof advanceof the stylus over the record, and means for supporting said unit in different positions on a record, in one of which said advanceball and said recording stylus engage the record, and in the other said reproducing stylus only engages said record.

.2. A combined electrical sound recorder and reproducer unit, comprising, in combination, a frame, a recording stylus carried by said frame, a reproducing stylus carried by said frame, reversible means for converting electric currents into mechanical vibrations associated with said styli, :an advance ball mounted on said frame, alongside said recording stylus, and means for selectively supporting saidunit in different positions .on

a record, in one of which said advance ball and said recording stylusengage said record, and in the other said reproducing stylus only engages said record.

. 3. A combined electrical sound recorder and reproducer unit comprising, in combination, a frame, a recording stylus carried by said frame, a reproducing stylus carried by said frame, reversible means for converting electric currents into mechanical vibrations associated with said styli, an advance ball mounted onsaid frame alongside said recording stylus, an arm for supporting said unit in different positions .on a record, in one of which said advance ;ball .and said recording stylus engage said record, and in the other said reproducing stylus only engages said record, said arm :being pivotally secured to .a support at. a :point substantially on a tangent to the record surface.

4:. A combined electrical sound recorder and reproducer unitcompr-ising, in combination, a frame, a recording stylus carried by said ,frame, a reproducing stylus carried by said frame, reversible means for converting electric currents into mechanical vibrations associated with said styli, an advance ball mounted on said frame alongsidezsaid recording stylus in such position that a line joining the recording stylus and advance ball defines the line ofadvance of saidstylus across the record, the height of said :advance ball being less than the height 01' said stylus, whereby said advance ball does not engage said record until after said recording stylus has-engaged said record, and

means for supporting said unit indifferent positions on said frame, in one of which said advance ball and said recording stylus engage said record and in the other of which said reproducing stylus only engages said record.

5. A combined electrical sound recorder and reproducer unit comprising, in combination, a frame, a recording stylus carried by said frame, a reproducing stylus carried by said frame, reversible means for converting electric currents into mechanical vibrations associated with said styli, an advance ball mounted on said frame alongside said recording stylus and in'such position that a line joining the recording stylus and advance ball defines the line of advance of said stylus across the record, the height of said advance ball being less than theheight'ofsaid recording stylus, whereby saidadvance balls does not engage said record until after said record ing stylus is in contact therewith, said advance ball and said recording stylus being displaced from the center of said unit, and means for supporting said unit in different positions on a record, in one of which said recording stylus and advance ball engage said record, and in the other of which'said reproducing stylus only engages said record.

6. A combined electrical sound recorder and reproducer unit comprising in combination, a frame, a recording stylus carried by said frame, a reproducing stylus carried by said frame, reversible means for converting electric currents into mechanical vibrations associated with said styli, an advance ball mounted on said frame alongside said recording stylus and on a line passing through said recording stylus and normal to the tangent to the record groove at the point of contact with the said recording stylus and of such height that said recording stylus engages said record. before said advance ball, and means for supporting said unit in different positions on said record in one of which said recording stylus and advance ball engage said record, and in the other of which said April, 1931.

vance ball engage said record, and in the other of which said reproducing stylus only engages said record.

8 A combined electrical sound recording and reproducing unit for cylindrical records, comprising, in combination, a frame, a recording stylus carried by said frame, a rea pointon a line tangent to the surfaceof a record in recording position.

'This specification signed this 9th day of ORVILLE M. DUNNING.

reproducing stylus only engages said record.

7. A combined electrical sound recorder and reproducer uniticomprising in combination, a frame, a recording stylus carried by said frame, a reproducing stylus carried by said frame, reversible means for converting electric currents into mechanical vibrations associated with said styli, an advance ball mounted on said frame alongside said recording stylus, andon a line passing through said recording stylus and normal to the tangent to the record groove at the point of contact unit in either of two different positions, in

one of which said recording stylus andad- 

